{
  "bibcode": "2008GCN..7535....1P",
  "body": "D. A. Perley, J. S. Bloom (UC Berkeley) and H.-W. Chen (U Chicago) report:\n\nWe have continued to monitor the optical afterglow of GRB 080319B from \nGemini-South.  Additional images were taken on UT March 21, 25, and 28. \n  Despite the presence of the Moon and low elevation of the target, the \nafterglow remains detected in all filters.  We report on photometry, \ncalibrated to SDSS DR6, as follows (including an improved analysis of \nimages obtained on UT March 20, previously reported in GCN 7486).\n\nt(hr)  filt mag   err\n24.808  g   20.83 0.05\n25.099  r   20.53 0.02\n25.363  i   20.37 0.03\n25.686  z   20.32 0.04\n\n48.653  r   21.56 0.03\n\n144.553 g   23.59 0.15\n144.886 r   23.49 0.09\n145.220 i   23.13 0.06\n145.553 z   23.48 0.11\n\n216.703 r   23.56 0.06\n217.036 i   23.28 0.06\n\nThe object appears visibly extended at late times, with a possible \nprojection extending to the south; this may be the host galaxy of this \ngamma-ray burst.  The imaging was acquired under variable seeing \nconditions and we caution that the presence of an underlying host may \ncomplicate the photometry.\n\nWhile roughly consistent with simple power-law decay of alpha=1.2-1.3 \n(e.g. GCN 7438, Li et al.), in detail the observations deviate slightly \nfrom a simple power-law, including a flattening in the last two sets of \nobservations that may be due host galaxy light (and possibly a small \namount of supernova contribution.)\n\nIn addition, we note the presence of a very red source at an offset of \n2.65\" (slightly west of south) from the afterglow.  Preliminary \nphotometry of this object gives the following:\n\ng = 24.3  +/- 0.2  (marginal detection)\nr = 23.76 +/- 0.06\ni = 22.55 +/- 0.03\nz = 21.71 +/- 0.03\n\nThis offset corresponds to 21 kpc at a redshift of 0.937 (Vreeswijk et \nal., GCN 7451).  It is dominated by a bright PSF-like center but also is \nvisibly extended to the south.  It may be an intervening absorber.\n\nFurther follow-up is planned and encouraged.",
  "circularId": 7535,
  "createdOn": 1206785460000,
  "email": "dperley@astro.berkeley.edu",
  "subject": "GRB 080319B: Continued Gemini-South followup and possible host galaxy",
  "submitter": "Daniel Perley at U.C. Berkeley  <dperley@astro.berkeley.edu>",
  "eventId": "GRB 080319B"
}